innate levitation and penalties

[Kershek]

The SRD on Levitate says:

A levitating creature who attacks with a melee or ranged weapon finds itself increasingly unstable; the first attack has an attack roll penalty of –1, the second –2, and so on, up to a maximum penalty of –5. A full round spent stabilizing allows the creature to begin again at –1.

Should this penalty be imposed on an air genasi, who gains levitate 1/day?

How about a Mind Flayer, who can do it at will?

Would it be considered that both can ignore the penalties since it's an innate abillity that they should be used to?

 

[AuraSeer]

Unless otherwise specified, a spell-like ability functions in all ways like the spell it duplicates. Genasi and illithids do suffer the cumulative attack penalty.

The problem is a limitation of the levitate effect. The magic only grants vertical movement, not horizontal control or stability. When you swing, throw, or fire a weapon, the recoil pushes you horizontally, and you start wobbling in the air. So it's a question of the magic's capabilities, not of whether you're used to it.

An analogy: If you're riding a horse at full gallop, you suffer a -8 on ranged attack rolls. Even if you do the same maneuver every day, it's still more difficult than shooting while standing still, hence the penalty.

(IIRC, there does exist a feat that removes the penalties for firing from horseback. If your DM agrees, you could create a feat that reduces or eliminates the penalties from levitation. That'd be a house rule though, and you still wouldn't get it for free.)